EDEN PRAIRIE, Minn. - At the time of his release a year ago former Vikings punter Chris Kluwe took the high road, saying he didn't think his high-profile activism was the reason for his being dismissed.

Now, it seems, Kluwe is changing his tune.

In a letter he wrote on April 30, published Thursday on Deadspin.com, Kluwe labeled former head coach Leslie Frazier and current Vikings General Manger Rick Spielman as cowards, and blasted special teams coach Mike Priefer as a bigot. Kluwe wrote that he suspects he was released from the Vikings due to his public stance in support of gay marriage.

Kluwe says his letter was written following the NFL draft when the team selected another punter, a signal to him that the Vikings were done dealing with him.

"The following is a record of what happened to me during my 2012 season with the Minnesota Vikings, written down immediately after the 2013 draft in April, when I realized what was happening, and revised recently only for clarity," Kluwe writes. "I tried to keep things as objective as possible, and anything you see in quotes are words that I directly recall being said to me."

In the letter Kluwe alleges that Frazier twice attempted to silence his public comments in support of gay marriage, recalling that his head coach told him "a wise coach once told me there are two things you don't talk about in the NFL, politics and religion."

Kluwe says that throughout the fall of 2012 special teams coach Mike Priefer repeatedly used homophobic language in his presence, something he had not done before Kluwe started commenting publicly on gay marriage.

"He would ask me if I had written any letters defending 'the gays' recently and denounce as disgusting the idea that two men would kiss, and he would constantly belittle or demean any idea of acceptance or tolerance," Kluwe writes in Deadspin.com. "I tried to laugh these off while also responding with the notion that perhaps they were human beings who deserved to be treated as human beings. Mike Priefer also said on multiple occasions that I would wind up burning in hell with the gays, and that the only truth was Jesus Christ and the Bible. He said all this in a semi-joking tone, and I responded in kind, as I felt a yelling match with my coach over human rights would greatly diminish my chances of remaining employed. I felt uncomfortable each time Mike Priefer said these things. After all, he was directly responsible for reviewing my job performance, but I hoped that after the vote concluded in Minnesota his behavior would taper off and eventually stop."

Instead, the former punter alleges, Priefer became increasingly homophobic. Kluwe alleges that in a meeting later that fall that Priefer went on an anti-gay rant.

"As we sat down in our chairs, Mike Priefer, in one of the meanest voices I can ever recall hearing, said: "We should round up all the gays, send them to an island, and then nuke it until it glows," Kluwe writes. "The room grew intensely quiet, and none of the players said a word for the rest of the meeting. The atmosphere was decidedly tense. I had never had an interaction that hostile with any of my teammates on this issue—some didn't agree with me, but our conversations were always civil and respectful. Afterward, several told me that what Mike Priefer had said was 'messed up.'"

In his open letter Kluwe says that Spielman sent him a message to "please fly under the radar please" after the punter tweeted about Pope Benedict stepping down due to his stance against same-sex marriage.

Kluwe maintains that both Spielman and Frazier lacked the fortitude to deal with Priefer, and that his dismissal was not related to performance. He also said he never plans to kick again, and that his motivation for writing the letter is so Priefer will never hold another NFL coaching position again.

The Minnesota Vikings released this statement Thursday afternoon:

"The Minnesota Vikings were made aware of Chris Kluwe's allegations for the first time today. We take them very seriously and will thoroughly review this matter.

As an organization, the Vikings consistently strive to create a supportive, respectful and accepting environment for all of our players, coaches and front office personnel. We do not tolerate discrimination at any level.

The team has long respected our players' and associates' individual rights, and, as Chris specifically stated, Vikings ownership supports and promotes tolerance, including on the subject of marriage equality. Because he was identified with the Vikings, Chris was asked to be respectful while expressing his opinions. Team ownership and management also repeatedly emphasized to Chris that the Vikings would not impinge on his right to express his views.

Any notion that Chris was released from our football team due to his stance on marriage equality is entirely inaccurate and inconsistent with team policy. Chris was released strictly based on his football performance.

We will have further comment at the appropriate time."